Optimum pH to Flocculate Construction Sediment

Sediment from construction sites can degrade the quality of water and endanger the livelihood of many creatures from aquatic worms to fish to human beings. Coagulation and Flocculation of construction sediments is a useful treatment method to protect the quality of rivers. However, the complexity of the process stems from the coagulant dosage and the pH level. This research focuses on finding the optimum pH for Ferric Chloride to receive the most efficient result in flocculating construction sediments. Standard practices for coagulation-flocculation, taken from drinking water treatment design, is used for mixing methods and the constant amount of Ferric Chloride dosage is determined by observation. The preliminary results suggest that the optimum pH is 6.0. While the efficiency of the water treatment revolves around the drop of turbidity and settling time, the evaluations of the system require an extensive amount of work as water treatment technologies are brought to construction sites, stormwater treatments and surface water discharges. Other factors, such as the disposal of post-mixing sediments, are considered for the evaluation of the overall quality of the system